1. Field of the Invention
The invention relates to deceleration control apparatus and method for a vehicle, and more particularly, to deceleration control apparatus and method that enable increases and decreases in a target deceleration to be set appropriately.
2. Description of the Related Art
A deceleration control apparatus for a vehicle has been proposed which has target deceleration controlling means for increasing and decreasing a target deceleration, and which controls a braking force in accordance with the target deceleration set by that target deceleration controlling means. The apparatus disclosed in JP(A) 2000-245016 is one example of such a deceleration control apparatus. This apparatus is provided with an E position for a shift lever. By shifting the shift lever to a Decel side (i.e., a side which promotes deceleration) or a Can-Decel side (i.e., a side which suppresses deceleration) in this E position, a target deceleration is either increased or decreased while shift control in the automatic transmission, as well as powering torque or regenerative torque control in an electric motor, is performed to generate a predetermined braking force in accordance with that target deceleration.
Conventional deceleration control apparatuses, however, uniformly set the rate of change in the target deceleration with respect to an operation of the shift lever (i.e., target deceleration setting means) such that, for example, when the shift lever is shifted once to the Decel side, the target deceleration increases only a certain amount. Therefore, when the rate of change is slow, such as when the amount of change is small, the operation time for setting the target deceleration increases. On the other hand, when the rate of change is fast, it is difficult to set the desired target deceleration and the target deceleration may become too large. Thus, there is still room for improvement with respect to setting increases and decreases in the target deceleration.